Light emitting element, a light emitting device, a method of manufacturing a light emitting element and a method of manufacturing a light emitting device

ABSTRACT

The present invention provides a light-emitting element, a method of manufacturing the light-emitting element, a light-emitting device, and a method of manufacturing the light-emitting device. A method of manufacturing a light-emitting element includes: forming a first conductive layer of a first conductive type, a light-emitting layer, and a second conductive layer of a second conductive type on at least one first substrate, forming an ohmic layer on the second conductive layer and bonding the at least one first substrate to a second substrate. The second substrate being larger than the first substrate. The method further includes etching portions of the ohmic layer, the second conductive layer, and the light-emitting layer to expose a portion of the first conductive layer.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from Korean Patent Application No.10-2008-0047575 filed on May 22, 2008, the disclosure of which is herebyincorporated herein in its entirety.

BACKGROUND

1. Technical Field

The present disclosure relates to a light-emitting element, a method ofmanufacturing the light-emitting element, a light-emitting device, andto a method of manufacturing the light-emitting device.

2. Description of the Related Art

For example, a small substrate with a size of less than about 6 inchesis typically used to manufacture light-emitting elements, such as an LED(light emitting diode) and an LD (laser diode). This is because it maybe difficult to fabricate a substrate with a size of about 6 inches ormore that is used to manufacture the light-emitting elements.

The use of the small substrate may lower throughput, which in turn maymake it difficult to reduce the manufacturing costs of thelight-emitting element. In addition, manufacturing equipment suitablefor a small substrate such as a substrate with a size of about 6 inchesor less should be used to manufacture a light-emitting element. As aresult, it may be necessary to develop manufacturing equipment suitablefor a small substrate.

SUMMARY OF THE INVENTION

Exemplary embodiments of the present invention may provide a method ofmanufacturing a light-emitting element with high throughput.

Exemplary embodiments of the present invention may provide a method ofmanufacturing a light-emitting device using the method of manufacturinga light-emitting element.

Exemplary embodiments of the present invention may provide alight-emitting element fabricated by using the method of manufacturing alight-emitting element.

Exemplary embodiments of the present invention may provide alight-emitting device manufactured by using the light-emitting element.

In accordance with an exemplary embodiment of the present invention, amethod of manufacturing a light-emitting element is provided. The methodincludes forming a first conductive layer of a first conductive type, alight-emitting layer, and a second conductive layer of a secondconductive type on at least one first substrate, forming an ohmic layeron the second conductive layer, and bonding the at least one firstsubstrate to a second substrate. The second substrate being larger thanthe first substrate. The method further includes etching portions of theohmic layer, the second conductive layer, and the light-emitting layerto expose a portion of the first conductive layer.

In accordance with another exemplary embodiment of the presentinvention, a method of manufacturing a light-emitting element isprovided. The method includes performing a first annealing on at leastone insulating substrate at a first temperature, and bonding the atleast one insulating substrate to a conductive substrate. The conductivesubstrate being larger than the insulating substrate. The method furtherincludes performing a second annealing on the insulating substrate andthe conductive substrate bonded to each other at a second temperaturethat is lower than the first temperature.

In accordance with still another exemplary embodiment of the presentinvention, a method of manufacturing a light-emitting element isprovided. The method includes forming a first GaN layer of an n type, alight-emitting layer, a second GaN layer of a p type on at least onesapphire substrate, performing a first annealing on the at least onesapphire substrate, forming an ohmic layer on the second GaN layer,performing a second annealing on the at least one sapphire substrate,and bonding the at least one sapphire substrate to a silicon substrate.The silicon substrate being larger than the sapphire substrate. Themethod further includes etching portions of the ohmic layer, the secondGaN layer, and the light-emitting layer to expose a portion of the firstGaN layer, forming a first electrode on the exposed first GaN layer andforming a second electrode on the ohmic layer.

In accordance with yet another exemplary embodiment of the presentinvention, a method of manufacturing a light-emitting device using themethod of manufacturing a light-emitting element according to theabove-mentioned aspects is provided.

In accordance with still yet another exemplary embodiment of the presentinvention, a light-emitting element is provided. The light elementincludes a substrate, a first conductive pattern of a first conductivetype formed on the substrate, a light-emitting pattern formed on thefirst conductive pattern, a second conductive pattern of a secondconductive type formed on the light-emitting pattern and an ohmicpattern formed on the second conductive pattern, wherein the width ofthe first conductive pattern is larger than that of the light-emittingpattern, and the edge of the second conductive pattern is aligned withthe edge of the ohmic pattern.

In accordance with yet still another exemplary embodiment of the presentinvention, a light-emitting device includes the light-emitting elementaccording to the above-mentioned aspect is provided.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present invention can be understood in moredetail from the following description taken in conjunction with theattached drawings, in which:

FIGS. 1 to 7 are diagrams illustrating intermediate steps of a method ofmanufacturing a light-emitting element according to a first exemplaryembodiment of the present invention;

FIGS. 8A and 8B are diagrams illustrating a light-emitting elementaccording to the first exemplary embodiment of the present invention;

FIG. 9 is a diagram illustrating a method of manufacturing alight-emitting element according to a second exemplary embodiment of thepresent invention;

FIG. 10 is a diagram illustrating a method of manufacturing alight-emitting element according to a third exemplary embodiment of thepresent invention;

FIGS. 11 and 12 are diagrams illustrating intermediate steps of a methodof manufacturing a light-emitting package according to the firstexemplary embodiment of the present invention;

FIGS. 13 and 14A to 14C are diagrams specifically illustratingconnection between a package body and a light-emitting element;

FIGS. 15 to 17 are diagrams illustrating light-emitting packagesaccording to second to fourth exemplary embodiments of the presentinvention;

FIG. 18 is a diagram illustrating a light-emitting system according tothe first exemplary embodiment of the present invention;

FIG. 19 is a diagram illustrating a light-emitting system according tothe second exemplary embodiment of the present invention;

FIGS. 20 to 21B are diagrams illustrating a light-emitting systemaccording to the third exemplary embodiment of the present invention;

FIG. 22 is a diagram illustrating a light-emitting system according tothe fourth exemplary embodiment of the present invention; and

FIGS. 23 to 26 are diagrams illustrating light-emitting systemsaccording to fifth to eighth exemplary embodiments of the presentinvention.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS OF THE INVENTION

The present invention will now be described more fully with reference tothe accompanying drawings, in which exemplary embodiments of theinvention are shown. The invention may, however, be embodied in manydifferent forms and should not be construed as being limited to theembodiments set forth herein. In the drawings, the size and relativesizes of layers and regions may be exaggerated for clarity.

It will be understood that when an element or layer is referred to asbeing “on”, “connected to” or “coupled to” another element or layer, itcan be directly on, connected or coupled to the other element or layeror intervening elements or layers may be present. In contrast, when anelement is referred to as being “directly on”, “directly connected to”or “directly coupled to” another element or layer, there are nointervening elements or layers present. Like numbers refer to likeelements throughout. As used herein, the term “and/or” includes any andall combinations of one or more of the associated listed items.

Spatially relative terms, such as “beneath”, “below”, “lower”, “above”,“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. In the specification, the samecomponents are denoted by the same reference numerals.

Exemplary embodiments of the present invention are described herein withreference to cross section illustrations that are schematicillustrations of idealized embodiments of the present invention. Assuch, variations from the shapes of the illustrations as a result, forexample, of manufacturing techniques and/or tolerances, are to beexpected. Thus, exemplary embodiments of the present invention shouldnot be construed as limited to the particular shapes of regionsillustrated herein but are to include deviations in shapes that result,for example, from manufacturing. For example, a region illustrated ordescribed as flat may, typically, have rough and/or nonlinear features.Moreover, sharp angles that are illustrated may be rounded. Thus, theregions illustrated in the figures are schematic in nature and theirshapes are not intended to illustrate the precise shape of a region andare not intended to limit the scope of the present invention.

Hereinafter, exemplary embodiments of the present invention will bedescribed in detail with reference to the accompanying drawings forclarity of the description of the prevent invention.

FIGS. 1 to 7 are diagrams illustrating intermediate steps of a method ofmanufacturing a light-emitting element according to a first exemplaryembodiment of the invention. FIGS. 8A and 8B are diagrams illustrating alight-emitting element according to the first exemplary embodiment ofthe invention.

First, referring to FIG. 1, a first conductive layer 112 a, alight-emitting layer 114 a, and a second conductive layer 116 a aresequentially formed on a first substrate 100.

The first conductive layer 112 a, the light-emitting layer 114 a, andthe second conductive layer 116 a may include, for example,In_(x)Al_(y)Ga_((1-x-y))N (0≦x≦1, and 0≦y≦1) (that is, various materialsincluding GaN). That is, the first conductive layer 112 a, thelight-emitting layer 114 a, and the second conductive layer 116 a may beformed of, for example, AlGaN or InGaN.

The first conductive layer 112 a, the light-emitting layer 114 a, andthe second conductive layer 116 a may be sequentially formed on thefirst substrate 100 by, for example, MOCVD (metal organic chemical vapordeposition), liquid phase epitaxy, hydride vapor phase epitaxy,molecular beam epitaxy, or MOVPE (metal organic vapor phase epitaxy).

Next, the layers will be described in detail. The first conductive layer112 a may be a first conductive type (for example, an n type), and thesecond conductive layer 116 a may be a second conductive type (forexample, a p type). However, the first conductive layer 112 a may be thesecond conductive type (p type), and the second conductive layer 116 amay be the first conductive type (n type) according to the design.

The light-emitting layer 114 a is a region in which carriers (forexample, electrons) of the first conductive layer 112 a are coupled tocarriers (for example, holes) of the second conductive layer 116 a toemit light. In addition, the light-emitting layer 114 a may include awell layer and a barrier layer. As the well layer has a band gap that isnarrower than that of the barrier layer, the carriers (the electrons andthe holes) are collected and coupled in the well layer. Thelight-emitting layer 114 a may be classified into, for example, a singlequantum well (SQW) structure and a multiple quantum well (MQW) structureaccording to the number of well layers. The single quantum wellstructure includes one well layer, and the multiple quantum wellstructure includes multiple well layers. To adjust emissioncharacteristics, at least one of the well layer and the barrier layermay be doped with, for example, at least one of B, P, Si, Mg, Zn, andSe.

The first substrate 100 may be formed of any material as long as it cangrow the first conductive layer 112 a, the light-emitting layer 114 a,and the second conductive layer 116 a. For example, the first substrate100 may be an insulating substrate that is formed of sapphire (Al₂O₃) orzinc oxide (ZnO), or a conductive substrate that is formed of silicon(Si) or silicon carbide (SiC). In the following description, the firstsubstrate 100 is composed of a sapphire substrate.

Also, a buffer layer may be formed between the first substrate 100 andthe first conductive layer 112 a. The buffer layer may be formed of, forexample, In_(x)Al_(y)Ga_((1-x-y))N (0≦x≦1, and 0≦y≦1). The buffer layeris formed to improve the crystallinity of the first conductive layer 112a, the light-emitting layer 114 a, and the second conductive layer 116a.

A base substrate having the first conductive layer 112 a, thelight-emitting layer 114 a, and the second conductive layer 116 a formedon the substrate 100 may be used.

Referring to FIG. 2, to activate the second conductive layer 116 a, thefirst substrate 100 having the first conductive layer 112 a, thelight-emitting layer 114 a, and the second conductive layer 116 a formedthereon may be subjected to a first annealing process 181. For example,the first annealing process 181 may be performed at a temperature ofabout 400° C. Specifically, for example, when the second conductivelayer 116 a is formed of In_(x)Al_(y)Ga_((1-x-y))N doped with Mg, thefirst annealing process 181 can reduce the amount of H coupled to Mg. Inthis way, it is possible to improve the p-type characteristics of thesecond conductive layer 116 a.

Referring to FIG. 3, an ohmic layer 130 a is formed on the secondconductive layer 116 a. For example, the ohmic layer 130 a may includeat least one of ITO (indium tin oxide), zinc (Zn), zinc oxide (ZnO),silver (Ag), tin (Ti), aluminum (Al), silver (Au), nickel (Ni), indiumoxide (In₂O₃), tin oxide (SnO₂), copper (Cu), tungsten (W), and platinum(Pt).

To activate the ohmic layer 130 a, a second annealing process 182 may beperformed on the first substrate 100 having the ohmic layer 130 a formedthereon. For example, the second annealing process may be performed at atemperature of about 400° C.

Referring FIGS. 4A and 4B, at least one first substrate 100 is bonded tothe second substrate 190.

Specifically, the second substrate 190 is larger than the firstsubstrate 100. That is, when the second substrate 190 overlaps the firstsubstrate 100, the second substrate 190 covers the first substrate 100so as to conceal the first substrate 100. For example, when the secondsubstrate 190 and the first substrate 100 have circular shapes, thediameter of the second substrate 190 is larger than that of the firstsubstrate 100. For example, the second substrate 190 may have a diameterof about 6 inches or more, that is, about 150 mm or more, and the firstsubstrate 100 may have a diameter of less than about 6 inches. When thesecond substrate 190 and the first substrate 100 have rectangularshapes, the diagonal of the second substrate 190 may be larger than thatof the first substrate 100.

The second substrate 190 may be a conductive substrate or an insulatingsubstrate. For example, the second substrate 190 may be a conductivesubstrate that is formed of at least one of silicon, strained silicon(Si), silicon alloy, SOI (silicon-on-insulator), silicon carbide (SiC),silicon germanium (SiGe), silicon germanium carbide (SiGeC), germanium,germanium alloy, gallium arsenide (GaAs), indium arsenide (InAs), aIII-V semiconductor, a II-VI semiconductor, compositions thereof, andlaminates thereof. In addition, the second substrate 190 may be, forexample, an insulating substrate that is formed of at least one ofaluminum nitride, boron nitride, silicon oxide, silicon nitride,beryllium nitride, quartz, compositions thereof, and laminates thereof.In the following description, the second substrate 190 is the siliconsubstrate.

Various bonding methods may be used to bond the first substrate 100 tothe second substrate 190. In the first exemplary embodiment of theinvention, direct bonding is used.

First, to directly bond the first substrate 100 to the second substrate190, the first substrate 100 and the second substrate 190 may satisfythe following conditions.

The bonding surfaces of the first substrate 100 and the second substrate190 should be substantially flat and smooth. When the bonding surfacesof the first substrate 100 and the second substrate 190 are curved orrough, it may be difficult to bond the two substrates.

That is, a total thickness variation may need to be adjusted so as to beequal to or smaller than a predetermined value. For example, in the caseof an 8-inch wafer, the total thickness variation may be equal to orless than about 6 μm. In the case of a 2-inch wafer, the total thicknessvariation may be equal to or less than about 1.5 μm.

Therefore, if necessary, a semiconductor polishing technique may be usedto polish at least one of the bonding surface of the first substrate 100and the bonding surface of the second substrate 190. For example, CMP(chemical mechanical polishing) may be used to adjust the surfaceroughness in the unit of A. It is preferable that the surfaceroughnesses of the bonding surface of the first substrate 100 and thebonding surface of the second substrate 190 be equal to or less thanabout 1 nm when they are measured by an AFM (atomic force microscope).The bonding surfaces of the first and second substrates 100 and 190 maybe mirror-polished.

In addition, the bonding surfaces of the first and second substrates 100and 190 should be well cleaned.

Therefore, if necessary, it is preferable that at least one of the firstsubstrate 100 and the second substrate 190 be well cleaned. The reasonis that various impurities adhered to the surfaces of the first andsecond substrates 100 and 190, such as particles and dust, may be acontamination source. That is, if there are impurities in an interfacebetween the first substrate 100 and the second substrate 190 during thebonding process therebetween, the bonding energy may be weakened. Whenthe bonding energy is weakened, the first substrate 100 may be readilydetached from the second substrate 190.

To directly bond the first substrate 100 and the second substrate 190,first, pre-treatment is performed on at least one of the bonding surfaceof the second substrate 190 and the bonding surface of the firstsubstrate 100.

The pre-treatment may be, for example, plasma treatment and/or wettreatment.

For example, the plasma treatment may use at least one of O₂, NH₃, SF₆,Ar, Cl₂, CHF₃, and H₂O, but is not limited thereto. As the plasmatreatment can be performed at a low temperature, it is possible toreduce stress applied to the first and second substrates 100 and 190.

The wet treatment may, for example, use at least one of H₂SO₄, HNO₃,HCl, H₂O₂, H₅IO₆, SC-1 (standard clean-1), and SC-2 (standard clean-2),but is not limited thereto. An SC-1 solution may be, for example,NH₄OH/H₂O₂, and an SC-2 solution may be, for example, HCl/H₂O₂.

The pre-treatment can activate the bonding surfaces of the first andsecond substrates 100 and 190. That is, the pre-treatment can change thestates of the bonding surfaces of the first and second substrates 100and 190 to be suitable for bonding.

A dangling bond may be generated on the bonding surface of the substratesubjected to the pre-treatment. The dangling bond may be a hydrophilicdangling bond or a hydrophobic dangling bond. For example, when thesecond substrate 190 is a silicon wafer and the first substrate 100 is asapphire wafer, “—OH”, which is a hydrophilic dangling bond, may beformed on the bonding surface of the first substrate 100 and the bondingsurface of the second substrate 190 by the pre-treatment.

Then, the second substrate 190 and at least one first substrate 100 arearranged such that their bonding surfaces face each other. At that time,“—OH” formed on the bonding surface of the first substrate 100 and “—OH”formed on the bonding surface of the second substrate 190 arespontaneously bonded to each other by the Van der Waals' force. As shownin the plan view of FIG. 4B, 9 first substrates 100 having a diameter ofabout 2 inches may be arranged on one second substrate 190 having adiameter of about 8 inches. The number of first substrates 100 arrangedon the second substrate 190 depends on a difference in size between thesecond substrate 190 and the first substrate 100.

Then, the second substrate 190 and the at least one first substrate 100that are spontaneously bonded to each other are subjected to, forexample, heat treatment or physical compression. Then, as shown in FIG.4A, the second substrate 190 and the at least one first substrate 100are connected to each other by a covalent bond. Specifically, when thesecond substrate 190 is a silicon wafer and the first substrate 100 is asapphire wafer, the second substrate 190 is coupled to a plurality offirst substrates 100 by an oxygen-oxygen covalent bond, as representedby the following chemical formula:

Si—OH+HO—Al₂O₃≡

Si—O—Al₂O₃+H₂O.

The heat treatment may be performed at a temperature in the range ofabout 25° C. (room temperature) to about 400° C. When the heat treatmentis performed at a high temperature for a long time, it is possible toincrease the bonding energy between the second substrate 190 and thefirst substrate 100. However, when the heat treatment is performed at anexcessively high temperature, the second substrate 190 and the firstsubstrate 100 are likely to be curved or cracked. Therefore, it may benecessary to perform the heat treatment in a proper temperature range.As the heat treatment time increases, the bonding energy may increase.However, even when the heat treatment time increases, the bonding energymay not increase after a specific time (for example, several hours) haselapsed. The reason is that, after a specific time has elapsed, “—OH”formed on the bonding surfaces of the second substrate 190 and theplurality of first substrates 100 may all be consumed (that is, this isbecause “—OH” may all be changed to the oxygen covalent bond). The heattreatment time may be adjusted, if necessary.

Referring to FIG. 5, the ohmic layer 130 a, the second conductive layer116, the light-emitting layer 114, and the first conductive layer 112are partially etched in this order to expose a portion of the firstconductive layer 112. As a result of the etching, an ohmic pattern 130,a second conductive pattern 116, a light-emitting pattern 114, and afirst conductive pattern 112 are formed, as shown in FIG. 5.

Referring to FIG. 6, an ohmic pattern 131 is formed on the exposed firstconductive pattern 112 (that is, a first electrode forming region) andthen a first electrode 140 and a second electrode 150 are formed. Forexample, the ohmic pattern 131 on the first conductive pattern 112 mayinclude at least one of ITO (indium tin oxide), zinc (Zn), zinc oxide(ZnO), silver (Ag), tin (Ti), aluminum (Al), gold (Au), nickel (Ni),indium oxide (In₂O₃), tin oxide (SnO₂), copper (Cu), tungsten (W), andplatinum (Pt).

Specifically, the first electrode 140 and the second electrode 150 maybe formed of the same material or different materials. For example, thefirst electrode 140 and the second electrode 150 may include at leastone of indium tin oxide (ITO), copper (Cu), nickel (Ni), chrome (Cr),gold (Au), titanium (Ti), platinum (Pt), aluminum (Al), vanadium (V),tungsten (W), molybdenum (Mo), and silver (Ag).

Then, the bonded first and second substrates 100 and 190 are subjectedto a third annealing process 183. In particular, the temperature of thethird annealing process 183 may be lower than that of the firstannealing process 181 and/or the second annealing process 182. Forexample, the third annealing process may be performed at a temperatureof about 190° C. or less.

For reference, the third annealing process 183 may be performed in thestage in which the first electrode 140 and the second electrode 150 arenot formed. Specifically, after the ohmic layer is formed on the firstelectrode 140, the third annealing process may be performed.

In particular, in the first exemplary embodiment of the invention, it ispreferable that processes after the bonding process (see FIGS. 4A and4B) be performed at a low temperature. The reason is as follows. Whenthe processes after the bonding process are performed at a hightemperature, the interfaces between the bonded first and secondsubstrates 100 and 190 may be stressed. When the amount of stress islarge, the first substrate 100 may be detached from the second substrate190. For this reason, it is preferable that high temperature processesbe executed before the bonding process. For example, the temperature ofthe third annealing process 183 may be lower than the temperature of thefirst annealing process 181 for activating the second conductive layer116 a and the temperature of the second annealing process 182 foractivating the ohmic layer 130 a.

Before or after the second electrode 150 is formed, a surface texturingprocess may be performed to form a texture shape on the surface of thesecond conductive pattern 116. The texture shape may be formed, forexample, by subjecting the surface of the second conductive pattern 116to wet etching using an etchant, such as KOH. The texture shape may beformed by, for example, dry etching. Light having an angle other than anescape cone angle may be confined in the second conductive pattern 116due to a difference in refractive index between the second conductivepattern 116 and air. The texture shape makes it possible for many lightcomponents to escape from the second conductive pattern 116. As aresult, it is possible to improve light emission efficiency.

Referring to FIG. 7, the second substrate 190 is removed.

For example, a grinding process or a CMP (chemical mechanical polishing)process may be used to remove the second substrate 190.

Then, the thickness of the first substrate 100 is reduced. For example,the CMP process may be performed to reduce the thickness of the firstsubstrate 100 to, for example, about 100 μm.

Then, a sawing process is performed to divide the substrate into chips,thereby completing a light-emitting element 1.

In the manufacturing process according to the first exemplary embodimentof the invention in which a plurality of first small substrates 100 arebonded to the second large substrate 190, only manufacturing equipmentsuitable for the size of the second large substrate 190 is used, butseparate manufacturing equipment for the first small substrates 100 isnot needed. In addition, as a large number of first substrates 100 aremanufactured at once, it is possible to improve throughput. As a result,it is possible to reduce the manufacturing costs of the light-emittingelement 1.

The light-emitting element 1 according to the first exemplary embodimentof the invention will be described with reference to FIGS. 7, 8A, and8B. The light-emitting element 1 according to the first exemplaryembodiment of the invention is manufactured by the manufacturing methoddescribed with reference to FIGS. 1 to 7.

Referring to FIGS. 7, 8A, and 8B, the light-emitting element 1 includesthe first conductive pattern 112, the light-emitting pattern 114 formedon the first conductive pattern 112, the second conductive pattern 116formed on the light-emitting pattern 114, and the ohmic patterns 130 and131 formed on the first conductive pattern 112 and the second conductivepattern 116. However, in the first exemplary embodiment of theinvention, the edge of the second conductive pattern 116 is aligned withthe edge of the ohmic pattern 130.

As described above, to decrease the temperatures of the processes afterthe bonding process (see FIGS. 4A and 4B), the ohmic layer 130 a isformed before the bonding process (see FIG. 3). Then, after the bondingprocess, the ohmic pattern 130, the second conductive pattern 116, thelight-emitting pattern 114, and the first conductive pattern 112 areetched at the same time (see FIG. 5). Therefore, the edge of the secondconductive pattern 116 is aligned with the edge of the ohmic pattern130.

Meanwhile, the light-emitting element 1 may be used for a top view typepackage and a side view type package. In the top view type package,generally, a rectangular light-emitting element having a size of, forexample, about 1 mm×1 mm shown in FIG. 8A is used. The top view typepackage directly emits light to an object, and is generally used for anilluminating device and a display device. On the other hand, in the sideview type package, a rectangular light-emitting element having, forexample, a size of about 150 μm×400 μm shown in FIG. 8B is used, but thestructure thereof may be changed depending upon the desired purpose. Theside view type package is generally used for a mobile device (forexample, a mobile phone, an MP3 player, and a navigation system) and adisplay device. The top view type package and the side view type packagemay be different from each other in size and shape, but substantiallysimilar to each other in configuration and operation.

Next, the operation of the light-emitting element 1 will be described.

When the first conductive pattern 112 is an n type and the secondconductive pattern 116 is a p type, a first bias (V−, I−, or the groundvoltage) is applied to the first conductive pattern 112 through thefirst electrode 140 and a second bias (V+ or I+) is applied to thesecond conductive pattern 116 through the second electrode 150.Therefore, a forward bias is applied to a light-emitting structure 110.The forward bias causes the light-emitting pattern 114 to emit light.

FIG. 9 is a diagram illustrating a method of manufacturing alight-emitting element according to a second exemplary embodiment of theinvention. FIG. 10 is a diagram illustrating a method of manufacturing alight-emitting element according to a third exemplary embodiment of theinvention.

Referring to FIGS. 9 and 10, the method of manufacturing thelight-emitting element according to the second and third exemplaryembodiments differs from that according to the first exemplaryembodiment in that the first substrate 100 is not directly bonded to thesecond substrate 190, but rather the first substrate 100 is bonded tothe second substrate 190 by an adhesive. In the adhesive bonding,intermediate material layers 191 and 192 are interposed between thefirst substrate 100 and the second substrate 190. When the intermediatematerial layer 191 has a sufficient thickness, the intermediate materiallayer 191 can compensate for the slight curvature of the first substrate100 or the second substrate 190.

The intermediate material layers 191 and 192 may be formed on thebonding surface of the second substrate 190 and/or the bonding surfaceof the first substrate 100, and the first substrate 100 and the secondsubstrate 190 may be bonded to each other by, for example, thermalcompression or physical compression. In FIGS. 9 and 10, for theconvenience of explanation, the intermediate material layer 191 isformed on the bonding surface of the second substrate 190.

As shown in FIG. 9, the intermediate material layer 191 may be, forexample, a metal layer that is formed of a conductive material. Forexample, the metal layer may include at least one of Au, Ag, Pt, Ni, Cu,Sn, Al, Pb, Cr, and Ti. That is, the metal layer may be, for example, asingle layer formed of Au, Ag, Pt, Ni, Cu, Sn, Al, Pb, Cr, or Ti, alaminate thereof, or a composition thereof. For example, the metal layermay be an Au layer, an Au—Sn layer, or a multilayer formed byalternately laminating Au and Sn layers.

As shown in FIG. 10, the intermediate material layer 192 may be anorganic layer. The organic layer may be, for example, BCB(benzocyclobutene). The BCB has been sold as Dow Cyclotene. The BCB issuitable to manufacture a semiconductor device. As the BCB is highlyresistant to most of wet etchants, it may be difficult to remove theBCB. In general, the BCB is removed usually only by dry etching. The BCBmay generate less stress than a silicon oxide (SiO₂). That is, even whenthe BCB is formed with a large thickness, the second substrate 190 maynot be curved or cracked.

Next, a method of manufacturing a light-emitting device using the methodof manufacturing the light-emitting element according to the first tothird exemplary embodiments of the invention will be described. Examplesof the light-emitting device include a light-emitting package (see FIGS.11 to 17) manufactured using the light-emitting element and alight-emitting system (see FIGS. 18 to 25) manufactured using thelight-emitting element and/or the light-emitting package.

FIGS. 11 and 12 are diagrams illustrating intermediate steps of a methodof manufacturing the light-emitting package according to the firstexemplary embodiment of the invention. For clarity of the description ofthe invention, FIGS. 11 and 12 simply show main parts. FIG. 13 and FIGS.14A to 14C are diagrams illustrating connection between a package bodyand a light-emitting element in detail. FIGS. 14A to 14C arecross-sectional views taken along the line XIV-XIV of FIG. 13.

First, referring to FIG. 11, the light-emitting element 1 is arranged ona package body 210.

Specifically, the package body 210 may include a slot 212 therein, andthe light-emitting element 1 may be provided in the slot 212. Inparticular, a side wall 212 a of the slot 212 may be inclined. Lightemitted from the light-emitting element 1 may be reflected from the sidewall 212 a and then travel forward.

In the drawings, the light-emitting element 1 is connected to a submount 230, and the light-emitting element 1 connected to the sub mount230 is provided in the slot 212 of the package body 210. However, theexemplary embodiments of the present invention are not limited thereto.For example, the light-emitting element 1 may be directly provided onthe package body 210 without using the sub mount 230.

Various methods may be used to connect the package body 210 and thelight-emitting element 1. For example, connecting methods shown in FIG.13 and FIGS. 14A to 14C may be used.

Referring to FIGS. 13 and 14A, the light-emitting element 1 may bemounted to the sub mount 230. In the drawings, the light-emittingelement 1 is connected in a flip chip manner, but the exemplaryembodiments of the present invention are not limited thereto. Forexample, the light-emitting element 1 may be connected in a lateralmanner. In the flip chip connection, the first electrode and the secondelectrode are connected so as to face the bottom of the package. In alateral-type LED, the first electrode and the second electrode areconnected so as to face the upper surface of the package. In FIG. 13,the light-emitting element 1 has a rectangular shape used for the topview type package, but the exemplary embodiments of the presentinvention are not limited thereto. For example, the light-emittingelement 1 may have a rectangular shape used for the side view typepackage.

The light-emitting element 1 may be a UV light-emitting element 1 thatemits UV light or a blue light-emitting element 1 that emits blue light,that is, light having a blue wavelength.

The light-emitting element 1 is arranged in the slot 212 of the packagebody 210. The slot 212 is larger than the light-emitting element 1. Thesize of the slot 212 may be determined in consideration of the amount oflight which is emitted from the light-emitting element 1 and reflectedfrom the side wall 212 a of the slot 212, the reflection angle thereof,the kind of transparent resin (reference numeral 250 in FIG. 12) fillingthe slot 212, and the kind of phosphor layer (reference numeral 260 inFIG. 12). It is preferable that the light-emitting element 1 be arrangedat the center of the slot 212. When the distance between thelight-emitting element 1 and the side wall 212 a is constant, it is easyto prevent color irregularity.

The package body 210 may be formed of an organic material having highresistance, such as, for example, silicon resin, epoxy resin, acrylicresin, urea resin, fluororesin, or imide resin, or an inorganic materialhaving high resistance, such as glass or silica gel. In addition, thepackage body 210 may be formed of heat-resistant resin such that it isnot melted by heat during a manufacturing process. In addition, toreduce the thermal stress of resin, various fillers, such as, forexample, aluminum nitride, aluminum oxide, and a compound thereof, maybe mixed with the resin. The material forming the package body 210 isnot limited to resin. A portion (for example, the side wall 212 a) of orthe entire package body 210 may be formed of, for example, a metalmaterial or a ceramic material. For example, when the entire packagebody 210 is formed of a metal material, it may be relatively easy todissipate heat generated from the light-emitting element 1. FIG. 3Ashows the case in which the entire package body 210 is formed of a metalmaterial.

In addition, leads 214 a and 214 b electrically connected to thelight-emitting element 1 are provided in the package body 210. Thelight-emitting element 1 may be electrically connected to the sub mount230, and the sub mount 230 and the leads 214 a and 214 b may beconnected to each other by, for example, wires 216 a and 216 b,respectively. The leads 214 a and 214 b may be formed of a materialhaving high thermal conductivity to directly dissipate heat generatedfrom the light-emitting element 1 to the outside through the leads 214 aand 214 b.

The light-emitting package shown in FIG. 14B differs from thelight-emitting package shown in FIG. 14 a in that the sub mount 230 andthe leads 214 a and 214 b are not connected to each other by the wires(216 a and 216 b in FIG. 14A), but they are connected to each other byvias 232 that are provided in the sub mount 230.

Further, the light-emitting package shown in FIG. 14C differs from thelight-emitting package shown in FIG. 14A in that the sub mount 230 andthe leads 214 a and 214 b are not connected to each other by the wires(216 a and 216 b in FIG. 14A), but they are connected to each other by awiring line 234 that is provided on the upper, side, and rear surfacesof the sub mount 230.

The light-emitting package shown in FIG. 14B and the light-emittingpackage shown in FIG. 14C do not use any wire. Therefore, it is possibleto reduce the size of a light-emitting package.

As described with reference to FIGS. 13 to 14C, the invention can beapplied to various light-emitting packages. In the specification, thefollowing drawings simply show main parts to prevent the scope of theexemplary embodiments of the invention from being limited.

Referring to FIG. 12 again, the transparent resin layer 250 is formed onthe light-emitting element 1. Specifically, the transparent resin layer250 fills at least a portion of the slot 212. For example, as shown inFIG. 12, the transparent resin layer 250 may not completely fill theslot 212. The material forming the transparent resin layer 250 may notbe particularly limited as long as it can fill up the slot 212 of thepackage body 210. For example, the transparent resin layer 250 may beformed of an epoxy resin, a silicon resin, a hard silicon resin, amodified silicon resin, a urethane resin, oxetane resin, an acrylicresin, a polycarbonate resin, or a polyimide resin.

Then, the phosphor layer 260 is formed on the transparent resin layer250. The phosphor layer 260 may be formed of a mixture of a transparentresin 262 and a phosphor 264. The phosphor 264 dispersed in the phosphorlayer 260 absorbs light emitted from the light-emitting package 1 andconverts it into light with a different wavelength. Therefore, as thephosphor 264 is dispersed well, the emission characteristics areimproved. As a result, the wavelength conversion efficiency and thecolor mixture effect of the phosphor 264 can be improved.

For example, the phosphor layer 260 may be formed in the light-emittingpackage 11 to emit white light. When the light-emitting package 11 emitsblue light, the phosphor 264 may include a yellow phosphor, and it mayalso include a red phosphor to improve a color rendering index (CRI)characteristic. When the light-emitting package 11 emits UV light, thephosphor 264 may include all of the red, green, and blue phosphors.

The transparent resin 262 is not particularly limited as long as it canstably disperse the phosphor 264. For example, the transparent resin 262may be, for example, an epoxy resin, a silicon resin, a hard siliconresin, a modified silicon resin, a urethane resin, an oxetane resin, anacrylic resin, a polycarbonate resin, or a polyimide resin.

The phosphor 264 is not particularly limited as long as it can absorblight from the light-emitting element 1 and convert it into light havinga different wavelength. For example, the phosphor is preferably at leastone selected from the following materials: a nitride-based phosphor oran oxynitride-based phosphor that is mainly activated by a lanthanoidelement, such as Eu or Ce; an alkaline earth element halogen apatitephosphor, an alkaline earth metal element boride halogen phosphor, analkaline earth metal element aluminate phosphor, alkaline earth elementsilicate, alkaline earth element sulfide, alkali earth elementthiogallate, alkaline earth element silicon nitride, and germanate thatare mainly activated by a lanthanoid element, such as Eu, or atransition metal element, such as Mn; rare earth aluminate and rareearth silicate that are mainly activated by a lanthanoid element, suchas Ce; and an organic compound and an organic complex that are mainlyactivated by a lanthanoid element, such as Eu. Specifically, thefollowing phosphors may be used, but the exemplary embodiments of thepresent invention are not limited to thereto.

The nitride-based phosphors that are mainly activated by a lanthanoidelement, such as Eu or Ce include, for example, M2Si₅N₈:Eu (M is atleast one element selected from the group consisting of Sr, Ca, Ba, Mg,and Zn). In addition to M₂Si₅N₈:Eu, MSi₇N₁₀:Eu, M_(1.8)Si₅O_(0.2)N₈:Eu,M_(0.9)Si₇O_(0.1)N₁₀:Eu (M is at least one element selected from thegroup consisting of Sr, Ca, Ba, Mg, and Zn) may also be included.

The oxynitride-based phosphors mainly activated by a lanthanoid element,such as Eu or Ce, include, for example, MSi₂O₂N₂:Eu (M is at least oneelement selected from the group consisting of Sr, Ca, Ba, Mg, and Zn).

The alkaline earth element halogen apatite phosphors mainly activated bya lanthanoid element, such as Eu, or a transition metal element, such asMn, include, for example, M₅(PO₄)₃X:R (M is at least one elementselected from the group consisting of Sr, Ca, Ba, Mg, and Zn, X is atleast one element selected from the group consisting of F, Cl, Br, andI, and R is at least one element selected from the group consisting ofEu, Mn, and a combination of Eu and Mn).

The alkaline earth metal element boride halogen phosphors include, forexample, M₂B₅O₉X:R (M is at least one element selected from the groupconsisting of Sr, Ca, Ba, Mg, and Zn, X is at least one element selectedfrom the group consisting of F, Cl, Br, and I, and R is at least oneelement selected from the group consisting of Eu, Mn, and a combinationof Eu and Mn).

The alkaline earth metal element aluminate phosphors include, forexample, SrAl₂O₄:R, Sr₄Al₁₄O₂₅:R, CaAl₂O₄:R, BaMg₂Al₁₆O₂₇:R, andBaMgAl₁₀O₁₇:R(R is at least one element selected from the groupconsisting of Eu, Mn, and a combination of Eu and Mn).

The alkaline earth sulfide-based phosphors include, for example,La₂O₂S:Eu, Y₂O₂S:Eu, and Gd₂O₂S:Eu.

The rare earth aluminate phosphors mainly activated by a lanthanoidelement, such as Ce, include, for example, YAG phosphors having thecompositions of Y₃Al₅O₁₂:Ce, (Y_(0.8)Gd_(0.2))₃Al₅O₁₂:Ce,Y₃(Al_(0.8)Ga_(0.2))₅O₁₂:Ce, and (Y, Gd)₃(Al, Ga)₅O₁₂:Ce. The rare earthaluminate phosphors may also include, for example, Tb₃Al₅O₁₂:Ce andLu₃Al₅O₁₂:Ce wherein a part or the whole of Y is substituted with, forexample, Tb or Lu.

The alkaline earth element silicate phosphor may consist of silicate,and a representative example thereof is, for example, (SrBa)₂SiO₄:Eu.

Other phosphors include, for example, ZnS:Eu, Zn₂GeO₄:Mn, and MGa₂S₄:Eu(M is at least one element selected from the group consisting of Sr, Ca,Ba, Mg, and Zn, and X is at least one element selected from the groupconsisting of F, Cl, Br and I).

The above-mentioned phosphors may include, for example, at least oneelement selected from the group consisting of Tb, Cu, Ag, Au, Cr, Nd,Dy, Co, Ni, and Ti, instead of or in addition to Eu, if necessary.

Other phosphors having the same performance and effect as thosedescribed above may also be used.

FIGS. 15 to 17 are diagrams illustrating light-emitting packagesaccording to the second to fourth exemplary embodiments of theinvention. As those skilled in the art can derive a method ofmanufacturing the light-emitting packages according to the second tofourth exemplary embodiments of the invention from the method ofmanufacturing the light-emitting package according to the firstexemplary embodiment of the invention, a description thereof will beomitted.

First, referring to FIG. 15, a light-emitting package 12 according tothe second embodiment of the invention differs from that according tothe first exemplary embodiment in that a filter 280 is formed on thephosphor layer 260. The filter 280 absorbs light having a specificwavelength. For example, the filter 280 may absorb light that isprimarily emitted from the light-emitting element 1, and may not absorblight that is secondarily emitted from the phosphor layer 260. Thefilter 280 may be formed of a material that absorbs light having aspecific wavelength and dissipates heat. For example, the filter 280 maybe formed of an inorganic dye or an organic dye.

In particular, when the light-emitting element 1 emits UV light, a UVfilter 280 may be used. This is because an excessively large amount ofUV light may be harmful to the human body.

Referring to FIG. 16, a light-emitting package 13 according to the thirdexemplary embodiment of the invention differs from that according to thefirst exemplary embodiment in that the phosphor layer 260 is formed in alens shape. The phosphor layer 260 may have a predetermined curvature toimprove the diffusion characteristics and the extraction characteristicsof light emitted from the light-emitting element 1. In FIG. 16, thephosphor layer is formed in a convex lens shape, but it may be formed ina concave lens shape, if necessary.

Referring to FIG. 17, a light-emitting package 14 according to thefourth exemplary embodiment of the invention differs from that accordingto the first exemplary embodiment in that the transparent resin layer250 is formed on only the light-emitting element 1 and the sub mount230. The phosphor layer 260 is formed on the transparent resin layer 250so as to fill up the slot 212.

FIG. 18 is a diagram illustrating a light-emitting system according tothe first exemplary embodiment of the invention.

Referring to FIG. 18, a light-emitting system 21 according to the firstexemplary embodiment of the invention includes a circuit board 300 andthe light-emitting package 11 arranged on the circuit board 300.

The circuit board 300 includes a first conductive region 310 and asecond conductive region 320 that are electrically isolated from eachother. The first conductive region 310 and the second conductive region320 are provided on one surface of the circuit board 300.

The first conductive region 310 is electrically connected to the lead214 a of the light-emitting package 11, and the second conductive region320 is electrically connected to the lead 214 b of the light-emittingpackage 11. The first and second conductive regions 310 and 320 may berespectively connected to the leads 214 a and 214 b by solder.

FIG. 19 is a diagram illustrating a light-emitting system according tothe second exemplary embodiment of the invention.

Referring to FIG. 19, a light-emitting system 22 according to the secondexemplary embodiment of the invention differs from that according to thefirst exemplary embodiment in that the circuit board 300 includesthrough vias 316 and 326.

Specifically, the first conductive region 310 and the second conductiveregion 320 are formed on one surface of the circuit board 300 so as tobe electrically isolated from each other, and a third conductive region312 and a fourth conductive region 322 are formed on the other surfaceof the circuit board 300 so as to be electrically isolated from eachother. The first conductive region 310 and the third conductive region312 are connected to each other through the first through via 316, andthe second conductive region 320 and the fourth conductive region 322are connected to each other through the second through via 326. Thefirst conductive region 310 is electrically connected to the lead 214 aof the light-emitting package 11, and the second conductive region 320is electrically connected to the lead 214 b of the light-emittingpackage 11.

FIGS. 20 to 21B are diagrams illustrating a light-emitting systemaccording to the third exemplary embodiment of the invention. Inparticular, FIGS. 21A and 21B show an example in which a phosphor layer340 and a transparent resin 350 are formed on a light-emitting packagearray.

FIG. 20 shows a light-emitting package array having a plurality oflight-emitting packages 11 arranged on the circuit board 300 in alight-emitting system 23 according to the third exemplary embodiment ofthe invention.

The first conductive regions 310 and the second conductive regions 320extend in parallel to each other in the same direction on the circuitboard 300. The light-emitting packages 11 are provided between the firstconductive regions 310 and the second conductive regions 320. Aplurality of light-emitting packages 11 are arranged in parallel to eachother so as to extend in the direction in which the first conductiveregion 310 and the second conductive region 320 extend. The firstconductive region 310 is electrically connected to the lead 214 a of thelight-emitting package 11, and the second conductive region 320 iselectrically connected to the lead 214 b of the light-emitting package11. When a first bias is applied to the first conductive region 310 anda second bias is applied to the second conductive region 320, a forwardbias is applied to a light-emitting element in the light-emittingpackage 11, which causes the plurality of light-emitting packages 11 toemit light at the same time.

Referring to FIG. 21A, the phosphor layer 340 and the transparent resin350 may be formed in linear shapes. For example, when the light-emittingpackage 11 is arranged in the direction in which the first and secondconductive regions 310 and 320 extend as shown in FIG. 14A, the phosphorlayer 340 and the transparent resin 350 may also be arranged in thedirection in which the first and second conductive regions 310 and 320extend. The phosphor layer 340 and the transparent resin 350 may beformed so as to surround both the first conductive region 310 and thesecond conductive region 320.

Referring to FIG. 21B, the phosphor layer 340 and the transparent resin350 may be formed in dots. In this case, the phosphor layer 340 and thetransparent resin 350 may be formed so as to surround only thecorresponding light-emitting package 11.

FIG. 22 is a diagram illustrating a light-emitting system according tothe fourth exemplary embodiment of the invention.

FIG. 22 shows an example of an end product to which the light-emittingsystem described with reference to FIGS. 18 to 21B is applied. Thelight-emitting system may be applied to various apparatuses, such as,for example, an illuminating device, a display device, and a mobileapparatus (for example, a mobile phone, an MP3 player, and a navigationsystem). The device shown in FIG. 22 is an edge type backlight unit(BLU) used in a liquid crystal display (LCD). As the liquid crystaldisplay does not have a light source therein, the backlight unit is usedas a light source, and the backlight unit illuminates the rear surfaceof a liquid crystal panel.

Referring to FIG. 22, the backlight unit includes the light-emittingpackage 11, a light guide plate 410, a reflecting plate 412, a diffusionsheet 414, and a pair of prism sheets 416.

The light-emitting element 1 emits light. The light-emitting element 1may be a side view type. As described above, the light-emitting element1 is arranged in the slot of the package body 210 of the light-emittingpackage 11.

The light guide plate 410 guides light emitted to the liquid crystalpanel 450. The light guide plate 410 is formed of a transparent plasticmaterial, such as, for example, acrylic resin, and guides light emittedfrom the light-emitting element 1 to the liquid crystal panel 450 thatis provided above the light guide plate 410. Therefore, various patterns412 a that change the traveling direction of light incident on the lightguide plate 410 to the liquid crystal panel 450 are printed on the rearsurface of the light guide plate 410.

The reflecting plate 412 is provided on the lower surface of the lightguide plate 410 to reflect light emitted from the lower side of thelight guide plate 410 to the upper side. The reflecting plate 412reflects light that is not reflected by the patterns 412 a, which isprovided on the rear surface of the light guide plate 410, to theemission surface of the light guide plate 410. In this way, it ispossible to reduce light loss and improve the uniformity of lightemitted from the emission surface of the light guide plate 410.

The diffusion sheet 414 diffuses light emitted from the light guideplate 410 to prevent partial light concentration.

Trigonal prisms are formed on the upper surface of the prism sheet 416in a predetermined array. In general, two prism sheets are arranged suchthat the prisms deviate from each other at a predetermined angle. Inthis way, the prism sheets make light diffused by the diffusion sheet414 travel in a direction that is vertical to the liquid crystal panel450.

FIGS. 23 to 26 are diagrams illustrating light-emitting systemsaccording to the fifth to eighth exemplary embodiments of the invention.

FIGS. 23 to 26 show end products to which the above-mentionedlight-emitting system is applied. FIG. 23 shows a projector, FIG. 24shows a car headlight, FIG. 25 shows a streetlamp, and FIG. 26 shows alamp. The light-emitting elements 1 used for the lighting devices shownin FIGS. 23 to 26 may be a top view type.

Referring to FIG. 23, light emitted from a light source 510 passesthrough a condensing lens 520, a color filter 530, and a sharping lens540 and is then reflected from a digital micromirror device (DMD) 550.Then, the light reaches a screen 590 through a projection lens 580. Thelight-emitting element according to the above-described exemplaryembodiments of the invention is provided in the light source 510.

Having described the exemplary embodiments of the present invention, itis further noted that it is readily apparent to those of reasonableskill in the art that various modifications may be made withoutdeparting from the spirit and scope of the invention which is defined bythe metes and bounds of the appended claims.

1. A method of manufacturing a light-emitting element, the methodcomprising: forming a first conductive layer of a first conductive type,a light-emitting layer, and a second conductive layer of a secondconductive type on at least one first substrate; forming an ohmic layeron the second conductive layer; bonding the at least one first substrateto a second substrate, the second substrate being larger than the firstsubstrate; and etching portions of the ohmic layer, the secondconductive layer, and the light-emitting layer to expose a portion ofthe first conductive layer.
 2. The method of claim 1, furthercomprising: before the ohmic layer is formed, performing a firstannealing on the first substrate having the first conductive layer, thelight-emitting layer, and the second conductive layer formed thereon. 3.The method of claim 2, further comprising: forming a first electrode onthe exposed first conductive layer, forming a second electrode on theohmic layer; and performing an annealing on the first and secondsubstrates bonded to each other after the first and second electrodesare formed, wherein the process temperature of the annealing performedon the first and second substrate bonded to each other is lower thanthat of the first annealing.
 4. The method of claim 2, furthercomprising: before the bonding of the first and second substrates toeach other, performing second annealing on the first substrate havingthe ohmic layer formed thereon.
 5. The method of claim 4, furthercomprising: forming a first electrode on the exposed first conductivelayer, forming a second electrode on the ohmic layer; and performing athird annealing on the first and second substrates bonded to each otherafter the first and second electrodes are formed, wherein the processtemperature of the third annealing is lower than that of the secondannealing.
 6. The method of claim 1, further comprising: forming a firstelectrode on the exposed first conductive layer, forming a secondelectrode on the ohmic layer; removing the second substrate after thefirst and second electrodes are formed, reducing the thickness of thefirst substrate; and dividing the first substrate into chips.
 7. Themethod of claim 1, wherein the bonding of the at least one firstsubstrate to the second substrate is performed by at least one of directbonding and adhesive bonding.
 8. The method of claim 7, wherein: thedirect bonding includes: pre-treating a bonding surface of the secondsubstrate or a bonding surface of the at least one first substrate; andperforming a heat treatment on the second substrate and the at least onefirst substrate, or physically compressing the second substrate and theat least one first substrate.
 9. The method of claim 8, wherein thepre-treatment includes a plasma treatment or a wet treatment.
 10. Themethod of claim 8, further comprising: before the pre-treatment,polishing at least one of the bonding surface of the first substrate andthe bonding surface of the second substrate.
 11. The method of claim 8,further comprising: before the pre-treatment, cleaning the firstsubstrate and the second substrate.
 12. The method of claim 7, wherein:the adhesive bonding includes: interposing an intermediate materiallayer between the bonding surface of the second substrate and thebonding surface of the at least one first substrate; and performing aheat treatment on the second substrate and the at least one firstsubstrate, or physically compressing the second substrate and the atleast one first substrate.
 13. The method of claim 1, wherein the firstsubstrate is an insulating substrate, and the second substrate is aconductive substrate.
 14. The method of claim 1, wherein the firstconductive layer, the light-emitting layer, and the second conductivelayer each include In_(x)Al_(y)Ga_((1-x-y))N (0≦x≦1, and 0≦y≦1).
 15. Themethod of claim 1, wherein the first conductive type is an n type, andthe second conductive type is a p type.
 16. A method of manufacturing alight-emitting element, the method comprising: performing a firstannealing on at least one insulating substrate at a first temperature;bonding the at least one insulating substrate to a conductive substrate,the conductive substrate being larger than the insulating substrate; andperforming a second annealing on the insulating substrate and theconductive substrate bonded to each other at a second temperature thatis lower than the first temperature.
 17. The method of claim 16, furthercomprising: before the first annealing, sequentially forming a firstconductive layer of a first conductive type, a light-emitting layer, anda second conductive layer of a second conductive type on the insulatingsubstrate.
 18. The method of claim 17, further comprising: before thefirst annealing, forming an ohmic layer on the second conductive layer.19. The method of claim 18, further comprising: after the bonding of theat least one insulating substrate to a conductive substrate and prior tothe second annealing, sequentially etching portions of the ohmic layer,the second conductive layer, and the light-emitting layer to expose aportion of the first conductive layer; forming a first electrode on theexposed first conductive layer; and forming a second electrode on theohmic layer.
 20. The method of claim 16, wherein the bonding of the atleast one insulating substrate to the conductive substrate is performedby at least one of direct bonding and adhesive bonding.
 21. A method ofmanufacturing a light-emitting element, the method comprising: forming afirst GaN layer of an n type, a light-emitting layer, a second GaN layerof a p type on at least one sapphire substrate; performing a firstannealing on the at least one sapphire substrate; forming an ohmic layeron the second GaN layer; performing a second annealing on the at leastone sapphire substrate; bonding the at least one sapphire substrate to asilicon substrate, the silicon substrate being larger than the sapphiresubstrate; etching portions of the ohmic layer, the second GaN layer,and the light-emitting layer to expose a portion of the first GaN layer;forming a first electrode on the exposed first GaN layer; and forming asecond electrode on the ohmic layer.
 22. The method of claim 21, furthercomprising: before or after the first and second electrodes are formed,performing a third annealing on the sapphire substrate and the siliconsubstrate bonded to each other, wherein the process temperature of thethird annealing is lower than that of the first annealing or the secondannealing.
 23. A method of manufacturing a light-emitting device usingthe method of manufacturing a light-emitting element according toclaim
 1. 24-27. (canceled)